In a previous article I outlined my thoughts on the usefulness of early stage financial modelling (“Early Stage “What-if” Mine Economic Analysis – Its Valuable”). My observation was that it is useful to take a few days to build a simple cashflow model to help your team better understand your project.
By “simple” I mean really simple.
This blog describes one of the techniques that I use to take a super-quick look at any project; whether it is for a client wishing to understand his project at a high level; or whether it is a project that I have read about. There isn’t any actual study or production schedule available yet. Maybe there is only a mineral resource estimate available.
It takes about 10 minutes to plug the numbers into my template to get fast results. The image below is an example of the simple model that I use, but anyone can build one for themselves.
Screenshot of Simple Economic Model
I use the term one dimensional (“1D”) model since it doesn’t use the typical X-Y matrix with years across the top and production data down the page.
The 1D model simply relies simple on life of mine (“LOM”) totals to estimate the total revenue, total operating cost, and total profit. This determines how much capital expenditure the project can tolerate.
The only caveat is that you need to have some sense for operating and capital costs for similar projects. This analysis can be on both a pre-tax and simple after-tax basis.
Using estimated metal prices and recoveries, the first step is to calculate the incremental revenue generated by each tonne of ore (see a previous article “Ore Value Calculator – What’s My Ore Worth?”).
Next that revenue per tonne is multiplied by the total ore tonnage to arrive at the total revenue over the life of mine.
The second step is to determine the life of mine operating cost, and again this simple calculation is based on estimated unit operating costs multiplied by the total tonnages being handled.
The third step is to calculate the life of mine profit based on total revenue minus total operating cost.
The potential net cashflow would be calculated by deducting an assumed capital cost from the life-of-mine profit. The average annual cashflow is estimated based on the net cashflow divided by the mine life. An approximate NPV can be calculated by determining the Present Value of a series of annual payments at a certain discount rate.
The reasonableness of the 1D model will be examined via benchmarking and this will be summarized once completed. I will include a link to that future blog here.
You need to understand your project
One can easily evaluate the potential impact of changing metal prices, changing recoveries, ore tonnages, operating costs, etc. to see what the economic or operational drivers are for this project. This can help you understand what you might need in order to make the project viable.
Conclusion
The bottom line is that a 1D economic calculation is very simplistic but still provides a vision for the project. The next step in the economic modelling process would be a 2D model based on an annual production schedule. The 1D approach is just a quick first step in looking at the potential. You can do it even when you only know the head grades and some generalized orebody information.
The two ways you can apply the simple 1-D model are:
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evaluate the potential of early stage projects using cost inputs from other studies,
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examine a project’s sensitives (units costs, recoveries, prices) by calibrating your simple model to the published study (i.e. use the same parameters and make changes as needed.
The entire blog post library can be found at this LINK with topics ranging from geotechnical, financial modelling, and junior mining investing.
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Tailings dam stability is so important that in some jurisdictions regulators may be requiring that mining companies have third party independent review boards or third party audits done on their tailings dams. The feeling is that, although a reputable consultant may be doing the dam design, there is still a need for some outside oversight.
Nowadays most small companies do not develop their own in-house resource estimates. The task is generally awarded to an independent QP.
One downside to a third party review is the added cost to the owner.
Their corporate website states that they would pay, for a specified period of time, the claim fees/taxes related to existing mineral properties or related to the staking of new mineral properties.
Mining companies are constantly in the media with stories of cost over-runs, mine shutdowns, fatalities, strikes & protests, and environmental incidents.
The larger mining companies will always have their investors like pension funds and mutual funds, however the junior miners may be a different story.
One of the first steps in an open pit design is the pit optimization analysis. Pit optimization is used to define the most profitable pit shell for a given set of economic parameters. The economic parameters include the metal prices, processing recoveries, and site operating costs. Normally when optimization is done, a range of metal prices or Revenue Factors (“RF”) is used to develop a series of nested shells to understand how the pit will expand or contract with increasing or decreasing metal prices.
Once the optimization step is complete, mining engineers will then design the pit inside that shell, introducing benches and ramps. The pit design should mimic the selected optimized shell as closely as possible.
The WBS can provide the following information to the team:
Typically a WBS is developed for pre-feasibility and feasibility mining studies but is often ignored at the PEA stage. Some feel it is too detailed for that level of study. I don’t feel this is the case.
The bottom line is that regardless of the level of study, a WBS should always be created.
The RFP sent to bidding consultants should contain (at a minimum) the items listed below. A sole sourced study can have a scaled back RFP document, but many of these key items should be maintained.
If a company is competitively bidding the study, it can be easier to compare multiple proposals if certain parts are presented in the exact same format. Usually different consulting firms have their own proposal format, which is fine, however certain sections of the proposal should be made easily comparable.
Over the past few decades I have worked in different consulting roles; as an independent consultant; as a member of a large consulting team; and as owner’s representative managing consultants. I have worked on projects where the mining company has their own external consultants that they have worked with for years (decades), learning that there are roles for both the independent consultant and larger consulting firms.
Independent consultants part of the management team will differentiate themselves from large engineering firms in several ways.
In my personal experience I find that larger consultants are best suited for managing the large scale feasibility studies. This isn’t because they necessarily provide better technical expertise. Its because they generally have the internal project management and costing systems to manage the complexities of such larger studies.
For certain aspects of a feasibility study, one may get better technical expertise by subcontracting to smaller highly specialized engineering firms. However too much subcontracting may become an onerous task. Often the larger firms may be better positioned to do this.
One of the purposes of an early stage study is to see if the project has economic merit and would therefore warrant further expenditures in the future. An early stage study is (hopefully) not used to defend a production decision. The objective of an early stage study is not necessarily to terminate a project (unless it is obviously highly uneconomic).